2 Answers
2

Well, why do you need a function to remove the title. Simply delete the title in the Editor, and moreover if you've already created the page the slug is created anyway. So now you can safely delete the title in your Page Editor and the title will not appear. Remember though, that this has global impact - meaning the title will not appear across entire site.

If however you wish to remove the title only on the single-page, then create a new page template and remove the code the_title() in that new template. And then, assign that template to your page. The title will not appear on that page.

This doesn't work if you delete & create that page again from the admin panel. To be more scalable, better options are available. You could use custom fields which are then checked with the help of the ID or you might be storing the id's which to hide in theme options or somewhere else.